13. The effects of sorafenib on the developing human fetus at the recommended therapeutic dose are unknown. Women of child-bearing potential must agree to use adequate contraception prior to study entry and for the duration of study participation. Effective methods of birth control would include a barrier method (e.g. condoms, diaphragm) combined with spermicide, or an intrauterine device (IUD). Should a woman become pregnant or suspect she is pregnant while participating in this study, she should inform her treating physician immediately.